The harsh, ominous lands ravaged by a post-apocalyptic event provide fertile grounds for diverse personal drama to flourish within, hinged on how situations differ between survivors and, naturally, the condition of the world extending beyond them. Some embark on long journeys in search of food or refuge -- at times with younger or inexperienced people in tow -- while others hunker down in their relatively safe and sustainable areas, crafting different perspectives on the concepts of hope, compromised faith, and willpower in a desperate situation. Z for Zachariah, the latest film from Compliance writer-director Craig Zobel, unites both of these ideas into an isolated indie drama, focused on the arrival of a pair of wanderers from the sprawl of radiation-plagued lands onto the safe haven maintained by a young, abandoned country woman. Coping with unclear world-building and a stiff grip on complicated themes involving belief in a higher power, director Zobel constructs a meaningful, bracing depiction of the preservation of relationships and of mankind itself within beautifully-captured surroundings.

Based on the novel of the same name by Robert C. O'Brien, Z for Zachariah first depicts the scavenging efforts of Ann Burden (Margot Robbie) through the abandoned buildings near her valley-enclosed farm, showing her suited in makeshift protective gear. Once she arrives home, she's able to shed her suit and go about her business without the consequences of radiation, setting traps for game and cultivating a limited amount of produce. Believing herself to be alone in this miraculously preserved safe zone, she's taken aback after spotting someone in a state-of-the-art hazmat suit, an older scientist named John Loomis (Chiwetel Ejiofor). After patching John up following his arduous trek through the country's contamination, the two attempt to figure out a way to cohabitate, developing a tentative bond that's assisted by John's technical know-how and withdrawn attitude. Their budding partnership and the awkward implications of being a man-woman pair are put to the test upon the arrival of another drifter, Caleb (Chris Pine), a simpler working man who seems more compatible with Ann's down-home traits.

Z for Zachariah doesn't delve into the details of what precisely caused the lands beyond the valley to be plagued by radiation, allowing the audience to deduce what they will as they gaze upon the valley's verdant isolation. In essence, the post-apocalyptic events that shaped this setting are streamlined into the creation of a pocket of life separate from the expanses of imminent death, a reason for those that exist within this oasis to never leave and to exploit the resources that remain, be it their property of that of another. That vagueness, the unlikely preservation of this beautiful land and its tools in the wake of society's collapse, plants the seeds for the symbolic, higher-concept angle of the film, expanding into a conflict between science and religion. Highlighted by Adam and Eve imagery spotted in books and the presence of a church on Ann's land, it becomes clear that Zobel wishes to elevate an understated philosophical conversation into a core aspect of the character drama, evenhandedly touching on the practical outlooks and concessions involved with how both sides approach "survival" under the conditions.

Don't fret, though, because this conflict over "divine intervention" exists to provide another dimension to the dynamics at play in Z for Zachariah, chiefly powered by the delicate balance between trepidation and trust among these scant survivors of a post-apocalyptic environment. Ann's mixture of industriousness and idealism are galvanized by the wide-eyed naivete given to her by Margot Robbie, whose endearing fortitude takes shape through a thick rural American accent and precautious body language in situations outside her life experiences. Chiwetel Ejiofor channels an enigmatic trustworthiness through Loomis in response, accentuating the emotionally weathered aura carried around by the character due to his downhearted history. Within the dimly-lit house nestled in the idyllic countryside, their secluded chemistry evolves into something complex under the circumstances, taking considerate individuals who wouldn't normally get intimately involved and encouraging them to do so -- overlooking differences and forgiving transgressions -- as an result of cooperation and necessity.

Z for Zachariah only reaches its most absorbing peaks once Caleb auspiciously enters the equation, though, played with an earthy, devious temperament by the traditionally slick Chris Pine. Caleb's ability to say the right things -- especially involving his belief structure -- and act comfortably around Ann at a crucial juncture in her relationship with Loomis leaves one wondering whether the gristly local is manipulating the situation by playing a long game, or whether his rustic attitude simply goes misunderstood through the lens of suspicion. Director Zobel smartly exploits this cynicism as a source of mystery and interpretation while the trio figures things out over boozy dinners and treks throughout the valley, further complicating the surface-level thoughts that Caleb might simply be a better fit for the country girl instead of the awkward and emotionally confused scientist. Conflicts ensue over tolerance and territoriality that generate palpable tension, resulting in a restrained but poignant tempo within the scope of the contained drama.

In a gutsy creative move, Craig Zobel lets those wheels of ambiguity continue spinning throughout and after the conclusion of Z for Zachariah, asking those watching to evaluate their observations of these characters -- how they've changed, how they've stayed the same, what they're capable of -- in an ending that's bound to be polarizing among those who seek closure in their relationship dramas. Utilizing the twisted viewpoints on morality and honesty that follow with a catastrophic collapse of society, director Zobel allows the fate of all three individuals to hang in the audience's minds in a similar fashion to the fate of the world itself after a post-apocalyptic event. All those complicated, shifting impressions on the triangle of flawed survivors, the trust lost and gained and their dedication to a prosperous life on the farmland spared by the apocalypse, culminate into a deliberate yet strikingly well-crafted thought exercise that thrives on emotional and experiential context. Whether that's rewarding or cathartic enough at the end of the road will depend on the individual and their willingness to have faith.